Telephone-transmitter mouthpiece



J. W. HARRIS.

TELEPHONE TRANSMITTER MOUTHPIECE.

v APPLICATION FILED OCT-18,1916- 1,334,093.

Patented Mar. 16, 1920.

UNITED STATES PATENT oFFioE.

JONATHAN W. HARRIS, OFM ONTGLAIR, NEW JERSEY, ASSIGNOR TO WESTERNELECTRIC COMPANY, INCORPORATED, OF NEW YOR-K,N. Y., A CORPORATION OF NEWYORK.

TEIiEPI-IONE TRANSMITTTER' MOUTHPIECE.

Specification of Letters Patent. Patented Mar. 16, 1 920- AppiicationfiledOctober 18, 1916; Serial No. 126,236i

To all "whom it may concern Be it known that I, JONATHAN WV. HAR- ms, acitizen ofthe United States, residing at Montolair, in the county ofEssexand State of New Jersey, have invented certain new and usefulImprovements inTel'ephone- Transmitter Mouthpieces, of \VJhlChfthefollowing is a full, clear. concise, and exact description.

This invention relates to telephone mouthpieces and themethod of makingthem, and has for itsobject a mouthpiece which may be readily cleanedand one more durable and more easily manufactured than those commonly inuse at the present time.

The telephone mouthpieces of hard rubber or rubber-like compounds, whichhave heretofore been in common use, are objectionable because theysoften and lose shape when placed in hot water to be cleaned, and alsobecause they are easily broken or chipped in service. Those made ofporcelain or similar substances, which screw directly into theface-plate of the telephone transmitter, or into an adapter which isitself screwed or otherwise fastened to the transmitter face, havefailed to meet commercial requirements satisfactorily because thethreads are diflicult to produce with accuracy and are easily chipped,the broken particles therefrom often interfering with the operation ofthe transmitter. Mouthpieces wherein the porcelain or similar portion isheld to the trans mitter face-plate by a screw-threaded metal ferrule oradapter to which the porcelain is cemented, have been found to beunsatisfactory because of the difiiculty of procuring a cement whichwill not dissolve or lose its properties in boiling water, and becausethe cements have been found to harden to such an extent that thestructure is substantially rigid, resulting in a highpercentage ofchipped and broken mouthpieces under usual service conditions.

It is to eliminate all of the above objections that this inventioncontemplates a telephone mouthpiece wherein the porcelain or similarportion is secured to the adapter or ferrule by a resilient adhesivebinder which is insoluble in water at ordinary boiling temperatures.More specifically, the invention contemplates a mouthpiece wherein aporcelain or similar body-portion is secured to a metal adapter orferrule by vulcanized rub- The invention will be fully understood fromthe following description taken in connection with the accompanyingdrawing wherein the preferred construction is illustrated, Figure 1showing the assembled structure partly in section; Figs. 2', 3 and 4:illustrating various details of the structure of-Fig. 1; and Fig. 5showing analternative structural arrangement Y A body-portion- 5 of theusual funnel shape, and preferably of porcelain, is provided at its basewith a contracted portion 6. This contracted portion is provided with aroughened surface which may be formed in the shape of a partialscrew-thread 7, as clearly shown in Fig. 2. The adapter or ferrule 9comprises a metal ring having an enlarged portion 10 and a contractedportion 11, as most clearly indicated in Figs. 1 and a. The contractedportion is outwardly threaded to engage the threads in the face-plate ofa telephone transmitter (not shown). The enlarged portion 10 isroughened on its inner surface in any desired manner to increase theadhesion between such surface and the binder 12.

The binder 12, which secures the bodyportion 5 and the adapter 9together, is preferably applied in the form of a band or strip of rubbercompound which, in assembling the structure, is wrapped around thecontracted portion 6 of the porcelain. It has been found that verysatisfactory results are obtained by using rubber compound sheetingabout of an inch in thickness, which is cut into strips of approximately3%- of an inch wide and about 3?; inches long. This strip is wrappedaround the constricted and threaded portion of the porcelain, and theferrule 9 is then pressed into place and held by a suitable clamp. Theassembled structure is then placed in an oven and kept at a temperatureof approximately 170 centigrade for one or two hours to vulcanize therubber. This process forms a resilient adhesive binder securelyfastening the porcelain and ferrule together. The structure is veryeasily assembled, and may be cleansed in boiling water without anyresulting damage. The resiliency of the rubber after vulcanization issufficient to enable it to absorb shocks resulting from very rough usageof the mouthpiece with a minimum danger of This is an arrangement whichunder some circumstances mayprove desirable for manufacturing reasons oras a means for improving the appearance of the mouthpiece.

V1 hat is claimed is:

1. The method of securing a ferrule to the body portion oi a telephonetransmitter mouthpiece which consists of inserting a re silient shockabsorbing member 0i Vulcanizable material therebctween and subjectingthe combined structure to a vulcanizing temperature.

2. The process of making telephone transmitter mouthpieces Whichconsists of interposing a resilient shock absorbing member ofvvulcanizable material between the body portion and the attaching memberand subjecting the combined structure to a vulcanizing temperature untilthe resilient member adhesively secures the attaching member to the bodyportion.

3. The method of securing the ferrule to the body portion of a telephonetrans mitter mouthpiece which consists of insert ing a layer of rubbercompound therebetween and subjecting the compound to a vulcanizingtemperature.

4. The method of securing an attaching member to the body portion of atelephone transmitter mouthpiece which consists of insorting a member ofVulcanizable material therebetween and subjecting the material to atemperature of approximately 170 centigrade for a period of from one totwo hours.

In witness whereof, I hereunto subscribe my name this 17th day ofOctober, A. D 1916.

JONATHAN WV. HARRIS.

